package com.example.demo.example;

import java.io.IOException;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Set;
import java.util.concurrent.CopyOnWriteArraySet;

import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;

import lombok.extern.slf4j.Slf4j;

import org.springframework.stereotype.Component;

@Slf4j
@ServerEndpoint(value = "/websocket/{userId}")
@Component
public class WebSocketServer {
    //静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。
    private static int onlineCount = 0;
    //concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
    private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();

    private static Hashtable<String, CopyOnWriteArraySet<WebSocketServer>> webSocketSetTable = new Hashtable<>();
    //与某个客户端的连接会话，需要通过它来给客户端发送数据
    private Session session;

    private static Hashtable<String, Set<Session>> sessions = new Hashtable<>();

    /**
     * 连接建立成功调用的方法
     */
    @OnOpen
    public void onOpen(@PathParam("userId") String userId, Session session) {
//        Set<Session> s = sessions.get(userId);
//        if (null == s) {
//            s = new HashSet<>();
//        }
//        s.add(session);
        this.session = session;
        log.info("uuid为" + userId + "的用户进来了！！！");
        CopyOnWriteArraySet<WebSocketServer> webSocketSet = webSocketSetTable.get(userId);
        if (null == webSocketSet) {
            webSocketSet = new CopyOnWriteArraySet<WebSocketServer>();
        }
        webSocketSet.add(this);
        webSocketSetTable.put(userId,webSocketSet);
        addOnlineCount();           //在线数加1
        log.info("有新连接加入！当前在线人数为" + getOnlineCount());
        try {
            sendMessage("连接成功");
        } catch (IOException e) {
            log.error("websocket IO异常");
        }
    }


    //  //连接打开时执行
    //  @OnOpen
    //  public void onOpen(@PathParam("user") String user, Session session) {
    //      currentUser = user;
    //      System.out.println("Connected ... " + session.getId());
    //  }

    /**
     * 连接关闭调用的方法
     */
    @OnClose
    public void onClose() {
        webSocketSet.remove(this);  //从set中删除
        subOnlineCount();           //在线数减1
        log.info("有一连接关闭！当前在线人数为" + getOnlineCount());
    }

    /**
     * 收到客户端消息后调用的方法
     *
     * @param message 客户端发送过来的消息
     */
    @OnMessage
    public void onMessage(String message, Session session) {
        log.info("来自客户端的消息:" + message);

        //群发消息
        for (WebSocketServer item : webSocketSet) {
            try {
                item.sendMessage(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * @param session
     * @param error
     */
    @OnError
    public void onError(Session session, Throwable error) {
        log.error("发生错误");
        error.printStackTrace();
    }


    public void sendMessage(String message) throws IOException {
        this.session.getBasicRemote().sendText(message);
    }

    public void sendMessageByUserId(String userId, String message) throws IOException {
        Set<Session> ss = sessions.get(userId);
        for (Session s : ss) {
            s.getBasicRemote().sendText(message);
        }
    }

    public static void sendMessageByUserId2(String userId, String message) throws IOException {
        Set<WebSocketServer> socketServers = webSocketSetTable.get(userId);
        if(null != socketServers){
            for (WebSocketServer item : socketServers) {
                try {
                    item.sendMessage(message);
                } catch (IOException e) {
                    continue;
                }
            }
        }
    }

    /**
     * 群发自定义消息
     */
    public static void sendInfo(String message) throws IOException {
        log.info(message);
        for (WebSocketServer item : webSocketSet) {
            try {
                item.sendMessage(message);
            } catch (IOException e) {
                continue;
            }
        }
    }

    public static synchronized int getOnlineCount() {
        return onlineCount;
    }

    public static synchronized void addOnlineCount() {
        WebSocketServer.onlineCount++;
    }

    public static synchronized void subOnlineCount() {
        WebSocketServer.onlineCount--;
    }
}
